Hello,
I have rebuilt a 289 for my 1967 cougar. It has comp cam, holley 4 barrel, and aluminum intake. I was wondering if anybody has any break in tips. I have seen a lot of different ideas on the internet. Some people say to baby the engine, some say not to let it idle or fall below 3,000 rpm. Any advice would help.
Thank you,
OldColts45
If you ask 10 people this question you’ll get 10 different answers.Listed is what has worked for me be the engine new or rebuilt, air or water cooled.This assuming the engine was built correctly.For cars I’ve used 30 wt.detergent oil unless the factory put something different in a brand new engine.
The 1st 50 miles I take easy. They will go fast because you’re all excited over the new motor.You’re checking to see how everything is and watching the gauges.
THEN I start running it up through the rpm range little by little up and down all over the range for the next 450 miles with that last 150-200 miles being at redline.When you accelerate you load one side of the rings and the other side when you decelerate.
Don’t get it hot.It could be said to break it in how you’ll drive it.When done put in 10-40 or whatever you want to run.
Answer #2… Built many an engine. Fun stuff. I’d say most important is the oil for break in. I use an oil additive with zinc. I use a Lucas engine break in additive with Valvoline Racing oil. Kind of expensive. I keep up the RPM’s around 2000 for 20 minutes but sometimes I have to lower RPMs if overheating so I can pour cold water from a hose through the cooling fins of the radiator without the fan sucking the water over your new engine. Most important is a good oil pressure to break in the camshaft at operating temperature. Make sure there isn’t a miss in the engine because that will wash the rings in the missing cylinder. Now to seat the rings yes I run the heck out of it for the first hour or so with a few instances of red lining it. If you really want to be anal drain the oil and change the filter but I run the break in oil for probably 10 hrs or so.
Nothing feels better to drive a fresh rebuilt engine you just ran the crap out of, it held together, and you did it yourself. And enjoy the smell of engine header/manifold paint curing and all the other smells. Good luck.
Answer #2-correct.Roller cam? Any good quality oil and no need for a certain rpm.Flat tappet"old fashioned "cam?Oil w/zinc or dedicated break-in oil.Revs for 2,000 for 20 minutes will be fine.Oil splash will lube lifters to cam lobe.About the roller cam-make sure you have the compatible gear on the distributor to mate with the material of that cam.
In the radiator I’ve just used water during break-in.If there’s a leak you don’t have to worry about capturing the 50/50 and the leak can be repaired.
Have a fire extinguisher handy just in case.Think SAFETY.Have someone there to watch things during initial fire-up.You’ll be fine.
Do exactly what the Comp Cams instructions say. Follow the instructions precisely.
Hello,
Thank all of you for the replies, If anything catastrophic happens when I try it, I will let you guys know!